Step 2 of 8
Templates over containers
Templates can take any parameter type, including containers of T:
template <typename T>
T sum(const std::vector<T>& v) {
T s{}; // T{} is "zero" for numbers, "" for strings
for (const auto& x : v) s += x;
return s;
}
Your turn: write template <typename T> int count_equal(const std::vector<T>& v, const T& value) that counts elements equal to value.